Function RunClassificationModel

samples/cpp/run_model/classification.cpp:98–221

run classification model

// run classification model
int RunClassificationModel(const Mat& src_img, const char* onnx_model_path) {
    /************************ 1. preprocess image *************************/
    const int32_t height = src_img.rows;
    const int32_t width = src_img.cols;
    const int32_t channels = src_img.channels();

    vector<float> in_data_(height * width * channels); // network need NCHW(RGB order) fp32 data
    float* in_data = in_data_.data();

    int32_t ret = ImagePreprocess(src_img, in_data); // convert NHWC to NCHW & substract mean div std
    if (ret != 0) {
        fprintf(stderr, "image preprocess failed!\n");
        return ret;
    }

    printf("image preprocess succeed!\n");

    /************************ 2. create runtime builder from onnx model *************************/
    auto x86_engine = x86::EngineFactory::Create(x86::EngineOptions()); // create x86 engine with default options
    unique_ptr<Engine> x86_engine_guard(x86_engine);

    // create onnx runtime builder according to onnx model & engines registered before
    auto builder = unique_ptr<onnx::RuntimeBuilder>(onnx::RuntimeBuilderFactory::Create());
    if (!builder) {
        fprintf(stderr, "create OnnxRuntimeBuilder from onnx model %s failed!\n", onnx_model_path);
        return -1;
    }

    // load onnx model
    auto status = builder->LoadModel(onnx_model_path);
    if (status != RC_SUCCESS) {
        fprintf(stderr, "init OnnxRuntimeBuilder failed: %s\n", GetRetCodeStr(status));
        return -1;
    }

    // register engines you want to use
    onnx::RuntimeBuilder::Resources resources;
    resources.engines = &x86_engine;
    resources.engine_num = 1;

    status = builder->SetResources(resources);
    if (status != RC_SUCCESS) {
        cerr << "onnx RuntimeBuilder SetResources failed: " << GetRetCodeStr(status) << endl;
        return -1;
    }

    status = builder->Preprocess();
    if (status != RC_SUCCESS) {
        fprintf(stderr, "builder preprocess failed: %s\n", GetRetCodeStr(status));
        return -1;
    }

    printf("successfully create runtime builder!\n");

    /************************ 3. build runtime *************************/
    // use runtime builder to build runtime, one builder can be used to build multiple runtimes sharing constant data &
    // topo here we only build one runtime for easy to understand
    unique_ptr<Runtime> runtime;